Sedation for gastrointestinal endoscopy in Australia: what is the same and what is different?

High-flow oxygen via oxygenating mouthguard in short upper gastrointestinal endoscopy: A randomised controlled trial

BACKGROUND

Anaesthetic care during upper gastrointestinal (GI) endoscopy has the unique challenge of maintaining ventilation and oxygenation via a shared upper airway. Supplemental oxygen is recommended by international society guidelines, however, the optimal route or rate of oxygen delivery is not known. Various oxygen delivery devices have been investigated to improve oxygenation during upper GI endoscopy, however, these are limited by commercial availability, costs and in some cases, the expertise required for insertion. Anecdotally at our centre, higher flows of supplemental oxygen can safely be delivered via an oxygenating mouthguard routinely used during upper GI endoscopic procedures.

AIM

To assess the incidence of hypoxaemia (SpO₂ < 90%) in patients undergoing upper GI endoscopy receiving supplemental oxygen using an oxygenating mouthguard at 20 L/min flow compared to standard nasal cannula (SNC) at 2 L/min flow.

METHODS

A single centre, prospective, randomised clinical trial at two sites of an Australian tertiary hospital between October 2020 and September 2021 was conducted. Patients undergoing elective upper gastrointestinal endoscopy under deep sedation were randomised to receive supplemental oxygen via high-flow via oxygenating mouthguard (HFMG) at 20 L/min flow or SNC at 2 L/min flow. The primary outcome was the incidence of hypoxaemia of any duration measured by pulse oximetry. Intraprocedural-related, procedural-related, and sedation-related adverse events and patient-reported outcomes were also recorded.

RESULTS

Three hundred patients were randomised. Eight patients were excluded after randomisation. 292 patients were included in the intention-to-treat analysis. The incidence of hypoxaemia was significantly reduced in those allocated HFMG. Six patients (4.4%) allocated to HFMG experienced an episode of hypoxaemia, compared to thirty-four (22.1%) patients allocated to SNC (P value < 0.001). No significant difference was observed in the rates of adverse events or patient-reported outcome measures.

CONCLUSION

The use of HFMG offers a novel approach to reducing the incidence of hypoxaemia during short upper gastrointestinal endoscopic procedures in low-risk patients undergoing deep sedation.

Effects of intravenous lidocaine on hypoxemia induced by propofol-based sedation for gastrointestinal endoscopy procedures: study protocol for a prospective, randomized, controlled trial

Background

Oxygen-desaturation episodes, blood pressure drops, and involuntary body movement are common problems that occur in propofol-based sedation in the procedure of painless gastrointestinal (GI) endoscopy. As a widely used analgesic adjuvant, intravenous lidocaine can reduce the consumption of propofol during ERCP or colonoscopy. However, it is still unknown how lidocaine affects the incidence of oxygen-desaturation episodes and cardiovascular events, and involuntary movement during painless GI endoscopy. Therefore, we aimed to assess the effectiveness and safety of intravenous lidocaine in propofol-based sedation for GI endoscopy.

Methods

We will conduct a single-center, prospective, randomized, double-blind, saline-controlled trial. A total number of 300 patients undergoing painless GI procedures will be enrolled and randomly divided into the lidocaine group (Group L) and the control group (Group C). After midazolam and sufentanil intravenous injection, a bolus of 1.5 mg/kg lidocaine was immediately injected and followed by a continuous infusion of 4 mg/kg/h in the lidocaine group, whereas the same volumes of saline solution in the control group. Then, propofol was titrated to produce unconsciousness during the procedure. The primary outcome will be the incidence of oxygen-desaturation episodes. Secondary outcomes will be the incidence of involuntary body movement, discomfort symptoms, propofol consumption, endoscopist, and patient satisfaction.

Discussion

Propofol-based deep sedation without intubation is widely used in painless GI endoscopy. However, adverse events such as hypoxemia often occur clinically. We expect to assess the effect of lidocaine on reducing the incidence of oxygen-desaturation episodes, cardiovascular events, and involuntary body movement. We believe that the results of this trial will provide an effective and safe method for painless GI endoscopy.

Trial registration

Chinese Clinical Trial Registry ChiCTR2100053818. Registered on 30 November 2021.

Sedation/analgesia techniques for nonoperating room anesthesia: new drugs and devices

PURPOSE OF REVIEW

The purpose of this article is to review new drugs and devices for nonoperating room anesthesia (NORA).

RECENT FINDINGS

Remimazolam is an ultra-short-acting, water-soluble intravenous benzodiazepine with a fast onset and offset that has been approved recently for use in procedural sedation. Phase III trials have established the effectiveness of remimazolam sedation compared with placebo and midazolam in gastrointestinal endoscopy and bronchoscopy. More research is required investigating remimazolam in real-world NORA settings, including comparisons with propofol sedation. Oliceridine is a μ-agonist with selectivity for the G protein pathway and low potency for β-arrestin recruitment. As such it may be associated with less nausea, vomiting and respiratory depression than traditional opioids used. Although no studies have been published about oliceridine use in NORA to date, results from surgical studies indicate a potential place in nonoperating room practice. Research continues into alternative methods of drug delivery, such as patient-controlled sedation but no new devices are described.

SUMMARY

Further studies are required before these new drugs and devices are embraced in NORA.

[The Guideline "Sedation for Gastrointestinal Endoscopy"]

The guideline "Sedation for gastrointestinal endoscopy" (AWMF-register-no. 021/014) was published initially in 2008. Because of new and developing evidence, the guideline was updated in 2015. The aim of the guideline is to define the necessary structural, equipment and personnel requirements that contribute to minimizing the risk of sedation for endoscopy. In view of the high and increasing significance of gastrointestinal endoscopy, the guideline will remain highly relevant in the future. Essential aspects are the selection of sedatives/hypnotics, structural requirements, personnel requirements with regard to number, availability and training, management of complications and quality assurance. In this article, the development and evaluation of the evidence and its influence on the practical implementation, in particular for anaesthesia, are highlighted.

National survey on sedation for gastrointestinal endoscopy in 2758 Chinese hospitals

BACKGROUND

Although sedation during gastrointestinal endoscopy is widely used in China, the characteristics of sedation use, including regional distribution, personnel composition, equipment used, and drug selection, remain unclear. The present study aimed to provide insights into the current practice and regional distribution of sedation for gastrointestinal endoscopy in China.

METHODS

A questionnaire consisting of 19 items was distributed to directors of anaesthesiology departments and anaesthesiologists in charge of endoscopic sedation units in mainland China through WeChat.

RESULTS

The results from 2758 participating hospitals (36.7% of the total) showed that 9 808 182 gastroscopies (69.3%) and 4 353 950 colonoscopies (30.7%), with a gastroscopy-to-colonoscopy ratio of 2.3, were conducted from January to December 2016. Sedation was used with 4 696 648 gastroscopies (47.9%) and 2 148 316 colonoscopies (49.3%), for a ratio of 2.2. The most commonly used sedative was propofol (61.0% for gastroscopies and 60.4% for colonoscopies). Haemoglobin oxygen saturation (SpO₂) was monitored in most patients (96.1%). Supplemental oxygen was routinely administered, but the availability of other equipment was variable (anaesthesia machine in 64.9%, physiological monitor in 84.4%, suction device in 72.3%, airway equipment in 75.5%, defibrillator in 32.7%, emergency kit in 57.0%, and difficult airway kit in 20.8% of centres responding).

CONCLUSIONS

The sedation rate for gastrointestinal endoscopy is much lower in China than in the USA and in Europe. The most commonly used combination of sedatives was propofol plus an opioid (either fentanyl or sufentanil). Emergency support devices, such as difficult airway devices and defibrillators, were not usually available.

Prospective audit of the safety of endoscopist-directed nurse-administered propofol sedation in an Australian referral hospital

BACKGROUND AND AIM

Endoscopist directed nurse administered propofol sedation (EDNAPS) is widely considered to be safe and efficient, but there are limited data from the Australian health-care setting, and Australian sedation guidelines do not support the practice. Thus, we report data from a prospective audit of EDNAPS over a 6.5-year period in an Australian referral hospital.

METHODS

Consecutive endoscopic procedures performed between January 2013 and June 2019. Sedation protocol was an initial dose of midazolam 1-3 mg intravenously (i.v.) and propofol 10-50 mg i.v.. Further aliquots of propofol 10-30 mg i.v. were given as required. ProvationMD® endoscopic reporting system was used to prospectively record patient demographics, medication and dose, American Society of Anesthesiologist's (ASA) class, and sedation-related complications.

RESULTS

During the 78-month period, 28 051 eligible procedures were performed; 3093 procedures performed with anesthetic support or without EDNAPS were excluded. In total, 24 958 procedures with EDNAPS were analyzed including 7563 gastroscopies, 12 941 colonoscopies, 2932 gastroscopy and colonoscopy, 1440 flexible sigmoidoscopies, and 82 combined gastroscopy and flexible sigmoidoscopy. Of these, 9539 were ASA 1 (38.2%), 13 680 were ASA 2 (54.8%), 1733 were ASA 3 (6.9%), and 4 were ASA 4 (0.02%). Sedation-related complications occurred in 66 patients (0.26%), predominantly transient hypoxic episodes. No patient required intubation for an airway emergency, and there was no sedation-related mortality. Sedation-related complications increased with ASA class and were significantly more common with gastroscopy.

CONCLUSIONS

Endoscopist directed nurse administered propofol sedation is a safe way of performing endoscopic sedation in low-risk patients in the hospital setting.

LMA® Gastro™ Airway for endoscopic retrograde cholangiopancreatography: a retrospective observational analysis

Background

Various airway techniques have been employed for endoscopic procedures, with an aim to optimise patient outcomes by improving airway control and preventing hypoxia whilst avoiding the need for intubation. The LMA® Gastro™ Airway, a novel dual channel supraglottic airway technique, has been described as such a device. Its utility alongside sedation with low flow nasal cannula and general anaesthesia (GA) with intubation for endoscopic retrograde cholangiopancreatography (ERCP) procedures was evaluated.

Methods

Details of all the ERCPs performed in our institution from March 2017 to June 2018 were carefully recorded in the patients’ electronic case records. Data on the successful completion of ERCP through LMA® Gastro™ Airway; any difficulty encountered by the gastroenterologists; and adverse events were recorded. Episodes of hypoxia (SpO₂ < 92%) and haemodynamic parameters were compared across the three groups: LMA® Gastro™ vs. sedation with low flow nasal cannula vs. GA with an endotracheal tube (ETT).

Results

One hundred seventy-seven ERCP procedures were performed during the study period. The LMA® Gastro™ Airway was employed in 64 procedures (36%) on 59 patients. Of these 64 procedures, ERCP was successfully completed with LMA® Gastro™ Airway in 63 (98%) instances, with only one case requiring conversion to an endotracheal tube. This instance followed difficulty in negotiating the endoscope through LMA® Gastro™ Airway. No episodes of hypoxia or hypercapnia were documented in both LMA® Gastro™ and GA with ETT groups. One sedation case with nasal cannula was noted to have hypoxia. Adverse intraoperative events were recognised in 2 cases of LMA® Gastro™: one had minimal blood stained secretions from the oral cavity that resolved with suctioning; the other developed mild laryngospasm which resolved spontaneously within a few minutes.

Conclusion

In patients undergoing ERCP, the LMA® Gastro™ airway demonstrated a high success rate for ERCP completion. Ventilation was well maintained with minimal intraoperative and postoperative adverse events. This technique may have a role in higher risk groups such as high ASA (American Society of Anesthesiologists) status, or those with potential airway difficulties such as high body mass index and those with known or suspected sleep apnoea.